Photographic silver halide emulsions sensitized with quaternary ammonium salt and developer combinations



United States Patent PHOTOGRAPHIC SILVER HALIDE EMULSIONS SENSITIZED WITH QUATERNARY AMMONIUM SALT AND DEVELOPER COMBINATIONS Kenneth C. Kennard and Frederick J. Russell, Rochester,

N.Y., assignors to Eastman Kodak Company, Rochester, N.Y., a corporation of New Jersey No Drawing. Filed Aug. 17, 1961, Ser. No. 132,012

17 Claims. (Cl. 96-95) This invention concerns photographic silver halide emulsions, and more particularly, photographic silver ha- R N NH I ca lide emulsions containing novel combinations of sensitizing addenda.

It is well known in the photographic art that silver halide emulsions can be chemically sensitized with a variety of materials in order to increase their speed. Certain chemical sensitizers are believed to react with the silver halide to form on the surface of the silver halide minute amounts of silver sulfide, or of silver, or of other noble metals. In addition, other classes of compounds that apparently do not enter into chemical combination with the silver halide can be utilized to increase the sensitivity of photographic silver halide emulsion. Such sensitization reaches a limit beyond which further addition of sensitizer merely increases the fog of the photographic emulsion with constant or decreasing speed.

It is an object of this invention to provide novel photographic silver halide emulsions that have increased sensitivity.

It is another object of the invention to provide photographic silver halide emulsions containing novel synergistic combinations of sensitizing materials.

It is still another object of this invention to substantially increase the speed of photographic silver halide emulsions without increasing fog to objectionable levels.

These and other objects of the invention are accomplished by incorporating into photographic silver halide emulsions sensitizing amounts of a combination comprising: (1) a quaternary ammonium salt silver halide chemical sensitizer, and (2) a photographic silver halide de veloping agent such as a hydroquinone developing agent, with a compound capable of forming a bisulfite ion, or a 3-pyrazolidone developing agent, or combinations of such developing agents.

A wide variety of quaternary ammonium salts can be utilized in the sensitizer combinations of the invention, a wide variety of such sensitizers being known in the art. Bis-quaternary ammonium salt silver halide chemical sensitizing agents are more generally utilized, with the his pyridinium salts wherein the pyridine nucleus is linked together by a divalent radical having at least 7 carbon atoms being particularly useful. Suitable quaternary ammonium salts are disclosed in Carroll U.S. Patent 2,271,623, issued February 3, 1942; Carroll et al. U.S. Patent 2,288,- 226, issued June 30, 1942; Trivelli et al. U.S. Patent 2,419,975, issued May 6, 1947; Piper U.S. Patent 2,886,-

437, issued May 12, 1959; Beavers et al. U.S. Patent 2,940,851, issued June 14, 1960; Beavers et a1. U.S. Patent 3,212,899 Patented Oct. 19, 1965 2,940,855, issued June 14, 1960; Beavers et al. U.S. Patent 2,944,898, issued July 12, 1960; Carroll et al. U.S. Patent 2,944,900,issued July 12, 1960; Carroll et al. U.S. Patent 2,944,902, issued July 12, 1960; and others. A particularly useful class of quaternary ammonium salts are described in Reynolds and Steward application titled, Photographic Silver Halide Emulsions Sensitized With 1,l-Dimethylhydrazinium Salts, U.S. Serial No. 124,800 filed July 18, 1961, which is copending herewith. Reynolds and Stewart described l-alkyl-l,l-dimethylhydrazinium salts and a,w-alkylene bis(1,l-dimethylhydrazinium salts) having the formulas 6 I I X and. H N-NP. --N--NH 2X I 8 CH on,

wherein R is an alkyl radical generally having 2 to 20 carbon atoms, wherein R is an alkylene radical generally having 2 to 20 carbon atoms and X is an anion such as are derived from such acids as p-toluene sulfonic acid, perchloric acid, hydrochloric acid, hydrobromic acid etc. Typical quaternary ammonium salts of the sensitizer combinations of the invention include:

p-Xylene bis(acetamido dimethyl ammonium perchlorate),

l,2-ethylenebis( 1,1-dimethylhydrazinium perchlorate),

1,4-tetramethylenebis 1,1-dimethylhydrazinium perchlorate),

1,6-hexamethylenebis( 1,1-dimethylhydrazinium perchlorate),

I-n-decyI-lJ-dimethyl hydrazinium perchlorate,

Lauryltriethyl ammonium perchlorate,

N-heptoxymethyl pyridinium perchlorate,

n-Nonyl pyridinium perchlorate,

n-Decyl pyridinium perchlorate,

1,2-ethylenebis(dioxymethyl pyridium perchlorate),

1, IO-decamethylenebis (triethylammonium perchlorate) Oxybis(methyl pyridinium perchlorate),

Acetcarbohydrazide pyridinium chloride,

Malonyl dicarbohydrazido pyridinium bromide,

N-methyI-Z-carbohydrazyl pyridinium p-toluenesulfonate,

Decamethylene-a,w-bis(oxymethylpyridinium perchlorate),

Lauryl pyridinium perchlorate,

Lauryl pyridinium p-toluenesulfonate,

Decamethylene-bis-(oXymethyl-a-picolinium perchlorate),

Tetradecamethylene bis (pyridinium perchlorate),

n-Myristyl trimethylammonium-p-toluenesulfonate,

4,1l-diaza-3,12-dioXotetradecane-l,14-bis(pyridiuium perchlorate) 3,14-diaza-2,lS-dioxohexadecane-l,l6-bis(pyridinium perchlorate),

p-Phenylenebis(2-aza-3-oxotridecane pyridinium perchlorate),

5,12-dioxa-6,l1-dioxohexadecane-l,16-bis(pyridinium perchlorate) 7, l 8-dioxa-8, l7-dioXotetracosane-1,23-bis(pyridinium perchlorate),

7,10,13,16,l9-pentaoxa-6,20-dioxopentacosane-1,ZS-bis (pyridinium perchlorate) 12-oxa-1l-oxodocosane-1,22-bis(pyridinium perchlorate),

3 5,12-diaza-3,14-dioxa-4,13-dioxo-hexadecane-1,16-bis (trimethylammonium p-toluene sulfonate), 7,18-diaza-6,19-dioxotetracosane-1,24-bis(pyridinium perchlorate), 6,13-diaza-4,1S-dioxo-S,14-dioxo-octadecane-1,18-bis(nmethylpyridinium p-toluene sulfonate), 9,16-diaza-7,18-dioxa-8,17-dioxotetracosane-1,24-bis (pyridinium perchlorate), 3,10,l7,24-tetraza-5,8,19,22-tetroXa-4,9,18,23-tetroXohexacosane-1,26-bis(pyridinium perchlorate), 3,18-diaza-5,16-dioxa-4,17-dioxoeicosane-l,20-bis(pyridinium perchlorate), Tetraethoxyethylbis (pyridinium perchlorate) Octaethoxyethylbis (dimethyldodecylammonium perchlorate), Polypropoxypropyl-a,w-bis (pyridinium methane sulfonate), and numerous other quaternary ammonium salts or other onium salts such as described in Carroll and Allen US. Patent 2,288,226, issued June 30, 1942, known to those skilled in the art as photographic silver halide emulsion sensitizers can be used in our invention.

Also, a wide variety of 3-pyrazolidone silver halide developing agents can be utilized in the sensitizer combinations of the invention, a wide variety of such developers being known in the art. Suitable 3-pyrazolidone developing agents are disclosed in Kendall US. Patent 2,289,367 issued July 14, 1942; Wilson US. Patent 2,685,516, issued August 3, 1954; Allen et al. US Patent 2,772,282, issued November 27, 1956; and others.

Typical 3-pyrazolidone developing agents have the formula wherein R can be hydrogen atoms, hydrocarbon radicals such as alkyl heterocyclic or aryl groups including phenyl, naphthyl and substituted hydrocarbon groups; and wherein R R R and R can be hydrogen atoms, hydrocarbon radicals such as alkyl groups preferably containing 1 to 4 carbon atoms or aryl groups including phenyl, naphthyl and substituted hydrocarbon groups. However a wide variety of other 3-pyrazolidone silver halide developing agents can be utilized in the invention. As used herein the term 3-pyrazolidone silver halide developing agents refers to all of such developing agents and substituted derivatives thereof. Typical 3-pyrazolidone silver halide developing agents that can be suitably utilized include:

1-phenyl-3-pyrazolidone, 1-p-tolyl-3 pyrazolidone, 5-phenyl-3-pyrazolidone, 5-methyl-3 pyrazolidone, 1-p-chlorophenyl-3 pyrazolidone, 1-phenyl-5-phenyl-3 :pyrazolidone, 1-m-tolyl-3pyrazolidone, 1phenyl-S-methyl-3-pyrazolidone, 1-p-tolyl-5-phenyl-3 pyrazolidone, 1p-methoxyphenyl-3pyrazolidone, 1acetamidophenyl-3pyrazolidone, 1phenyl-Z-acetyl-4,4-dimethyl-3 pyrazolidone, 1-phenyl-4,4-dimethyl-3 pyrazolidone, 1m-aminophenyl-4-methyl-4-propyl-3pyrazolidone, 1-o-chlorophenyl-4-methyl-4-ethyl-3pyrazolidone, lm-acetarnidophenyl-4,4-diethyl-3 pyrazolidone, 1-(p-,8-hydroxyethylphenyl -4,4-dimethyl-3-pyrazolidone, lp-hydroxyphenyl-4,4-dimethyl-3 pyrazolidone, lp-methoxyphenyl-4,4-diethyl-3pyrazolidone, 1-p-tolyl-4,4-dimethyl-3 pyrazolidone, 1- 7-hydroxy-2-naphthyl -4-methyl-4-n-propyl-3- pyrazolidone,

4 1p-diphenyl-4,4-dimethyl-3-pyrazolidone, 1- (p-fl-hydroxyethylphenyl) 3-pyrazolidone, 1-o-tolyl-3-pyrazolidone, 1-o-tolyl-4,4-dimethyl-3pyrazolidone, 1-benzothiazolyl-3pyrazolidone and others.

A diversity of hydroquinone silver halide developing agents with compounds capable of releasing or forming bisulfite ions can be utilized in the present sensitizer combinations. Hydroquinone or substituted hydroquinones including such groups as alkyl, aryl and other hydrocarbons, carboxyl, acyl, acyloxy, alkoxy etc. The substituents on the hydroquinone suitably have 1 to 20 and more generally 1 to 6 carbon atoms. Typical hydroquinones include: hydroquinone, p-toluhydroquinone, 2,5-dihydroxybenzoic acid and the like. A particularly useful class of compounds that release bisulfite ions are alkali metal bisulfites such as sodium bisulfite and potassium bisulfite. Other suitable bisulfite ion-producing compounds include sodium sulfite and potassium sulfite. Sulphur dioxide also can be utilized as a source of bisulfite ions. Sulfur dioxide and hydroquinones form clathrates, and the sulfur dioxide and hydroquinone are preferably added to the emulsion in this form. Such clathrates were described by Mandelcorn in Chemical Reviews, 59, pp. 827-830, October 1959. The bisulfite forming compound usually comprises less than one-half by weight of the combined Weight of the hydroquinone and the bisulfite releasing compound, although larger amounts of bisulfite can be utilized. Preferably, at least about 5 molar percent of bilsulfite ion based on the hydroquinone is utilized. For optimum results, the hydroquinone and the compound capable of releasing or forming a bisulfite ion are admixed or combined prior to incorporation into photographic emulsions, although these compounds can be individually added to the emulsion.

The present sensitizer addenda are added to the photographic emulsions in sensitizing amounts as determined by methods well known in the art. Generally, however, about .01 to 10 and preferably .1 to 5 grams of the quaternary ammonium salt, about .01 to 10 and preferably .l to 5 grams of the 3-pyrazolidone developing agent, and about 1 to grams of the hydroquinone-bisulfite forming compound are utilized per mole of silver halide present in the emulsion.

The subject sensitizer addenda can be incorporated directly into the photographic silver halide emulsion layer or, alternatively, they can be utilized in contiguous layers.

The preparation of photographic silver halide emulsions such as are used with the addenda of this invention involves three separate operations: (1) emulsification and digestion of silver halide, (2) the freeing of the emulsion of excess Water-soluble salts, suitably by washing with water, and (3) the second digestion or after-ripening to obtain increased emulsion speed or sensitivity. (Mees, The Theory of the Photographic Process, 1954.) The addenda of the invention can be added to the emulsion before the final digestion or after-ripening, or they can be added immediately prior to the coating.

The addenda of the invention can be added to photographic emulsions using any of the well-known techniques in emulsion making. For example, they can be dissolved in a suitable solvent and added to the silver halide emulsion, or they can be added to the emulsion in the form of a dispersion similar to the technique used to incorporate certain types of color-forming compounds (couplers) in a photographic emulsion. Techniques of this type are described in Jelley et al. US. Patent 2,322,027, issued June 15, 1943, and Fierke et al. US. Patent 2,801,171, issued July 30, 1957. The solvent should be selected so that it has no harmful effect upon the emulsion in accordance with usual practice, and generally solvents or diluents which are miscible with water are to be preferred.

The emulsions can be digested with naturally active gelatin, or sulfur compounds can be added, such as those described in Sheppard U.S. Patent 1,574,944, issued March 2, 1926, and Sheppard et al. 1,623,499, issued April 5, 1927, and Sheppard and Brigham U.S. Patent 2,410,689, issued November 5, 1946. The emulsions can also be treated with salts of the noble metals such as ruthenium, rhodium, palladium, iridium and platinum. Representative compounds are ammonium chloropalladate, potassium chloroplatinate, and sodium chloropalladite, which are used for amounts below that which produce any substantial fog inhibition, as described in Smith and Trivelli U.S. Patent 2,448,060, issued August 31, 1948, and as antifoggants in higher amounts, as described in Trivelli and Smith U.S. Patents 2,566,245, issued August 2 8, 1951 and 2,566,263, issued August 28, 1951. The emulsions can also contain small amounts of gold salts as described in Waller et al. U. S. Patent 2,399,083, issued April 23, 1946, or in Damschroder U.S. Patent 2,597,856, issued May 27, 1952, and Yutzy and Leermakers U.S. Patent 2,597,915, issued May 27, 1952. Suitable compounds are potassium chloroaurite, potassium aurithiocyanate, potassium chloroaurate, auric trichloride and 2-aur-osulfobenzothiazole methochloride. The emulsions can also contain small amounts of reducing agents such as stannous salts (Carroll U.S. Patent 2,487,850, issued November 15, 1959), p-olyamines, such as diethylene triamine (Lowe and Jones U.S. Patent 2,518,698, issued August 15, 1950), polyamines, such as spermine (Lowe and Allen U.S. Patent 2,521,925, issued September 12, 1950), or bis(B-aminoethyl)sulfide and its water-soluble salts (Lowe and Jones U.S. Patent 2,521,926, issued September 12, 1950).

The emulsions can also be optically sensitized with cyanine and merocyanine dyes, such as those described in Brooker US. Patents 1,846,301, issued February 23, 1932; 1,846,302, issued February 23, 1932; and 1,942,854, issued January 9, 1934; White U.S. Patent 1,990,507, issued February 12, 1935; Brooker and White U.S. Patents 2,112,140, issued March 22, 1938; 2,165,338, issued July 11, 1939; 2,493,747, issued January 10, 1950; and 2,739,964, issued March 27, 1956; Brooker and Keyes U.S. Patent 2,493,748, issued January 10, 1950; Sprague U.S. Patents 2,503,776, issued April 11, 1950, and 2,519,- 001, issued August 15, 1950; Heseltine and Brooker U.S. Patent 2,666,761, issued January 19, 1954; Heseltine U.S. Patent 2,734,900, issued February 14, 1956; Van Lare U.S. Patent 2,739,149, issued March 20, 1956; and Kodak Limited British Patent 450,958, accepted July 15, 1936.

The emulsions can contain a suitable gelatin plasticizer such as glycerin; a dihydroxy alkane such as 1,5-pentanediol as described in Milton and Murray U.S. Patent 2,960,404, issued November 15, 1960; an ester of an ethylene bis-glycolic acid such as ethylenebis(rnethyl glycolate) as described in Milton U.S. Patent 2,904,434, issued September 15, 1959; bis(ethoxy diethylene glycol) succinate as described in Gray U.S. Patent 2,940,854, issued June 14, 1960, or a polymeric hydrosol as results from the emulsion polymerization of a mixture of an amide of an acid of the acrylic acid series, an acrylic acid ester and a styrene-type compound as described in Tong U.S. Patent 2,852,386, issued September 16, 1958. The plasticizer may be added to the emulsion before or after the addition of a sensitizing dye, if used.

The emulsion can be hardened with any suitable hardener for gelatin such as formaldehyde; a halogen-substituted aliphatic acid such as mucobr-omic acid as described in White U.S. Patent 2,080,019, issued May 11, 1937; a compound having a plurality of acid anhydride groups such as 7,8-diphenylbicyclo(2,2,2)-7-octene-2,3,5,6-tetracarboxylic dianhydride, or a dicarboxylic or a disulfonic acid chloride such as terephthaloyl chloride or naphthalene-1,5-disulfonyl chloride as described in Allen and Carroll U.S. Patents 2,725,294 and 2,725,295, both issued November 29, 1955; a cyclic 1,2-diketone such as cyclopentane-LZ-di-one as described in Allen and Byers U.S. Patent 2,725,305, issued November 29, 1955; a bisester of methane-sulfonic acid such as 1,2-di-(methansulfonoxy) ethane as described in Allen and Laakso U.S. Patent 2,726,162, issued December 6, 1955; 1,3-dihydroxymethylbenzhnidazol-Z-one as described in July, Knott and Pollak U.S. Patent 2,732,316, issued January 24, 1956; a dialdehyde or a sodium bis-ulfite derivative thereof, the aldehyde groups of which are separated by 2-3 carbon atoms, such as fl-methylglutaraldehyde bis-sodium bisul fite; a bisaziridine carboxamide such as trimethylenebis (l-aziridine carboxamide) as described in Allen and Webster U.S. Patent 2,950,197, issued August 23, 1960; or 2,3-dihydroxy dioxane as described in JeflFreys U.S. Patent' 2,870,013, issued January 20, 1959. A

The emulsions can contain a coating aid such as saponin; a lauryl or oleoyl monoether of polyethylene glycol as described in Knox and Davis U.S. Patent 2,831,766, issued April 22, 1958; a salt of a sulfated and alkylated polyethylene glycol ether as described in Knox and Davis U.S. Patent 2,719,087, issued September 27, 1955; an acylated alkyl taurine such as the sodium salt of N-oleoyl- N-methyl taurine as described in Knox, Twardokus and Davis U.S. Patent 2,739,891, issued March 27, 1956; the reaction product of a dianhydride of tetracarboxybutane with an alcohol or an aliphatic amine containing from 8 to 18 carbon atoms which is treated with a base, for example, the sodium salt of the monoester of tetracarboxybutane as described in Knox, Stenberg and Wilson U.S. Patent 2,843,487, issued July 15, 1958; a water-soluble maleopimarate or a mixture of a water-soluble maleopirnarate and a substituted glutamate salt as described in Knox and Fowler U.S. Patent 2,823,123, issued February 11, 1958; an alkali metal salt of a substituted amino acid such as disodium N-(carbo-p-tert. octylphenoxypentaethoxy) glutamate, or a sulfosuccinamate such as tetrasodium N 1,2 dicarboxyethyl) N 'octadecyl sulfosuccinamate, or N-lauryl disodium sulfosuccinamate.

The emulsions can also be stabilized with the mercury compounds of Allen, Byers, and Murray U.S. Patent 2,728,663, issued December 27, 1955; Carroll and Murray U.S. Patent 2,728,664, issued December 27, 1955; and Leubner and Murray U.S. Patent 2,728,665, issued December 27, 1955 and triazoles of Heimbach and Kelly U.S. Patent 2,444,608, issued July 6, 1948; the azaindenes of Heimbach and Kelly U.S. Patents 2,444,605, and 2,444,606, issued July 6, 1948; Heimbach U.S. Patents 2,444,607, issued July 6, 1948, and 2,450,397, issued September 28, 1948; Heimbach and Clark U.S. Patent 2,444,609, issued July 6, 1948; Allen and Reynolds U.S. Patents 2,713,541, issued July 19, 1955, and 2,743,181, issued April 24, 1956; Carroll and Beach U.S. Patent 2,716,062, issued August 23, 1955; Allen and Beilfuss U.S. Patent 2,735,769, issued February 21, 1956; Reynolds and Sagal US. Patent 2,756,147, issued July 24, 1956; Allen and Sagura U.S. Patent 2,772,164, issued November 27, 1956, and those disclosed by Birr in Z. wiss. Phot., vol. 47, 1952, pages 2-28; the disulfides of Kodak Belgian Patent 569,317, issued July 31, 1958; the quaternary benzothiazolium compounds of Brooker and Stand U.S. Patent 2,131,038, issued September 27, 1938; the bis-quaternary salts of Allen and Wilson U.S. Patent 2,694,716, issued November 16, 1954 (e.g., decamethylene bis-benzothiazolium perchlorate, etc.), and the zinc and cadmium salts of Jones U.S. Patent 2,839,405, issued June 17, 1958.

The sensitizing addena of the invention can be used in various kinds of photographic emulsions. In addition to being useful in orthochromatic, panchromatic, and infrared sensitive emulsions, they are also useful in X-ray and other non-optically sensitized emulsions. They can be added to the emulsion before or after any optical sensitizing dyes which may be used. Various silver salts can be used as the sensitive salt such as silver bromide, silver iodide, silver chloride, or mixed silver halides such as silver chlorobromide or silver bromoiodide. The subject addenda can be used in emulsions intended for color photography, for example, emulsions containing colorforming couplers or emulsions to be developed by solutions containing couplers or other color-generating materials, emulsions of the mixed-packet type, such as described in Godowsky U.S. Patent 2,698,794, issued Jannary 4, 1955, or emulsions of the mixed-grain type, such as described in Carroll and Hanson U.S. Patent 2,592,243, issued April 8, 1952. Suitable color couplers usually belong to three widely known types, i.e., pyrazolone couplers, phenol couplers and open-chain ketomethylene couplers which combine with the oxidation products of arcmatic primary amine silver halide developing agents to produce magenta, cyan and yellow images respectively. Development accelerators can be utilized in developing such color emulsions including polyethylene glycols, their ester derivatives, their ether derivatives typically having the formula RO(CH CH O),,H wherein R is an alkyl radical having 1 to 5 carbon atoms and wherein n is 15-100, and related derivatives. The subject addenda can also be used in emulsions which form latent images predominantly on the surface of the silver halide crystal or in emulsions which form latent images predominantly inside the silver halide crystal, such as those described in Davey and Knott U.S. Patent 2,592,250, issued April 8, 1952.

The subject addenda can also be used in emulsions intended for use in diffusion transfer processes which utilize the undeveloped silver halide in the non-image areas of the negative to form a positive by dissolving the undeveloped silver halide and precipitating it on a receiving layer in close proximity to the original silver halide emulsion layer. Such processes are described in Rott U.S. Patent 2,352,014, issued June 20, 1944, and Land U.S. Patents 2,584,029, issued January 29, 1952; 2,608,236, issued December 28, 1954, and 2,543,181, issued February 27, 1951. They can also be used in color transfer processes which utilize the diffusion transfer of an irnagewise distribution of developer, coupler or dye, from a light-sensitive layer to a second layer, While the two layers are in close proximity to one another. Color processes of this type are described in Land U.S. Patents 2,559,643, issued July 10, 1951, and 2,698,798, issued January 4, 1955; Land and Rogers Belgian Patents 554,933 and 554,934, granted August 12, 1957; International Polaroid Belgian Patents 554,212, granted July 16, 1957, and 554,935, granted August 12, 1957; and Yutzy U.S. Patent 2,756,- 142, issued July 24, 1956.

In the preparation of the silver halide dispersions employed for preparing silver halide emulsions, there can be employed as the dispersing agent for the silver halide in its preparation, gelatin or some other colloidal material material such as colloidal albumin, a cellulose derivative, or a synthetic resin, for instance, a polyvinyl com-pound, although gelatin is preferred. Some colloids which can be used are polyvinyl alcohol or a hydrolyzed polyvinyl acetate as described in Lowe U.S. Patent 2,286,215, issued June 16, 1942; a far hydrolyzed cellulose ester such as cellulose acetate hydrolyzed to an acetyl content of 1926% as described in U.S. Patent 2,327,808 of Lowe and Clark, issued August 24, 1943; a water-soluble ethanolamine cellulose acetate as described in Yutzy U.S. Patent 2,322,085, issued June 15, 1943; a polyacrylamide having a combined acrylamide content of 30-60% and a specific viscosity of 0.251.5 on an imidized polyacrylamide of like acrylamide content and viscosity as described in Lowe, Minsk and Kenyon U.S. Patent 2,541,- 474, issued February 13, 1951; zein as described in Lowe U.S. Patent 2,563,791, issued August 7, 1951; a vinyl alcohol polymer containing urethane carboxylic acid groups of the type described in Unruh and Smith U.S. Patent 2,768,154, issued October 23, 1956; or containing cyanoacetyl groups such as the vinyl alcohol-vinyl cyanoacetate copolymer as described in Unruh, Smith and Priest U.S. Patent 2,808,331, issued October 1, 1957; or a polymeric material which results from polymerizing a protein or a saturated acylated protein with a monomer having a vinyl group as described in Illingsworth, Dann and Gates U.S. Patent 2,852,382, issued September 19, 1958. If desired, compatible mixtures of two or more of these colloids can be employed for dispersing the silver halide in its preparation.

The above-described emulsions of the invention can be coated on a wide variety of supports in accordance with usual practice. Typical supports for photographic elements of the invention include cellulose nitrate film, cellulose acetate film, polyvinyl acetal film, polystyrene film, polyethylene terephthalate film and related films of resinous materials, as well as glass, paper, wood, metals and others.

The present invention is illustrated by photographic emulsions containing at least two of the following listed addenda, the addenda numbers below being used in specific examples and tables below to identify the addenda for purposes of convenience.

Addenda 7,l8-diaza-6,19-dioxotetrac0sane-l,24-bis(pyridiniu;u1

perchlorate).

l-n-deeyl-l,1-dimethyl hydrazinium perchlorate.

Hydroquinone-sulfur dioxide clathrate (10.6% by weight sulfur dioxide).

4-methyl-l-phenyl-3-pyrazolidone.

2,5-dihydroxybenzoic acid sulfur dioxide elathrate (7 86% by weight sulfur dioxide).

7,18-dioxa 8,17-diox0tetracosane-1,24-bis(pyridiniun1 perchlorate).

Tetradecamethylenebis (pyridinium perchlorate) 4-11-0ctyl-1-phenyl-3-pyraz0lidone.

1,2-ethylenebis(1,l-tlimethylhydraziniun1 perchlorate) 1,4-tetramethylenebis(Ll-dimethylhydrazinium perchlorate).

1,6-hexamethylenebis(1,1-dimethylhydrazinium perchlop-Xylenebis(aetamido dimethyl ammonium perchlo- 2-chloroacetyl-1-phenyl-3-pyrazo1idone. 2-ehloroacetyl-4-methyl-1-phenyl-3-pyrazolidone. 4-ethyl-1-phenyl-3-pyrazolidone.

4-methyl-2-phenoxyaeetyl-l-phenyl-3-pyrazolidone. 4-benzyl-l-phenyl-3-pyrazolidone.

EXAMPLE 1 Typical feature addenda of the invention were incorporated into samples of a high speed negative-type gelatino-silver bromoiodide emulsion that was sulfur and gold sensitized and panchromatically sensitized with cyanine dye. The silver halide in the emulsion consisted of about 96% by weight of silver bromide and about 4% by weight of silver iodide. About 200 grams of gelatin per mole of silver halide was present in the emulsion. The emulsion was coated at a coverage of about 700 mg. of silver per square foot, a cellulose acetate film support being utilized. The prepared photographic elements were then exposed in the form of film strips in an Eastman Ib sensitometer, developed for 6.5 minutes and then fixed, Washed and dried in the usual manner. Emulsions containing none of the feature addenda were also included in the tests for purposes of comparison. The developer had essentially the following formula:

G. N-methyl-p-aminophenol sulfate 2.5 Hydroquinone 2.5 Sodium sulfite (anhydrous) 30.0 Sodium borate 10.0 Potassium bromide 0.5

Table A Cone. of addenda (g./mole Coating AgX), Compound No. Relative sample speed Gamma Fog I II III IV V EXAMPLE 2 The invention was further illustrated by incorporating additional sensitizer combinations of the invention in a gelatino-silver bromoiodide emulsion as described in Example 1 and tested by the general procedure described in Example 1. In addition, the test emulsions were tested after 1 and 2 week incubation periods at 120 F. and 50% relative humidity. The results of the tests are summarized by the data set out in Tables B, C, D, E and F The same results as those illustrated by the data set out in Tables B, C, D, E and F above are obtained when an equivalent molar amount of sodium bisulfite is substituted for the sulfur dioxide in combination with the hydroquinone. Alkali metal bisulfites in combination with hydroquinone were found to be equivalent in the present sensitizer combinations to hydroquinone-sulfur dioxide clathrates such as exemplified by Compound II above.

EXAMPLE 3 The hydroquinone-sulfur dioxide clathrate (compound III) can be prepared by dissolving 110 g. of hydroquinone in 700 ml. of distilled water at C. The resulting solution is then saturated with sulfur dioxide and cooled to 5 C. A clathrate forms as yellow crystals which crystallize out of the reaction mixture and which are then filtered off and dried.

The developments of the test samples exposed in the sensitometer as described in the above examples were effected at 68 F.

As can be observed from the data set out in the tables in the above examples, a wide variety tertiary ammonium salt silver halide chemical sensitizers in combination with a wide variety of hydroquinone silver halide developing agents in combination with a compound capable of forming a bisulfite ion or 3-pyrazolidone silver halide developing agents, or mixtures of such developing agents, cooperate to substantially increase the speed of photographic silver halide emulsions. If substantial or extreme below. 30 amounts of quarternary ammonium salt silver halide Table B Original test 1 week incubation 2 week incubation Feature addenda, g. [mole AgX Rel. 'y Fog Rel. 'y Fog Rel. 'y Fog speed speed speed Control (contains 1.0 g. Compound I plus 15 g. Compound III) 100 97 13 113 .90 .13 91 24 Control plus 1.0 g. Compound IV 132 1. 08 13 138 1.02 16 123 .94 26 Control plus 1.5 g. Compound VIII 126 14 138 94 13 78 24 Control plus 3.0 g. Compound VIIL- 132 .99 14 138 91 14 110 70 24 Control plus 0.5 g. Compound XVIL 138 1.00 30 105 92 15 151 .93 19 Control plus 1.5 g. Compound XVII. 141 1.15 38 182 1. 04 15 159 99 23 Control plus 1.5 g. Compound XVI 132 1. 05 14 129 1.00 .11 132 97 .14 Control plus 0.5 g. Compound XV- 148 1. 11 24 141 1. 05 15 151 97 19 Control plus 1.5 g. Compound XV 174 1.18 28 178 1. 26 14 162 .99 24 Table C Original test 1 week incubation 2 week incubation Feature addenda, gJmole AgX Rel. 'y Fog Rel. 7 Fog Rel. 7 Fog speed speed speed Control 100 96 13 78 .18 95 71 18 Control plus 1.0 g. Compound I plus 15 g. Compound III plus 1.0 g. Compound II 135 1. 16 17 178 1.14 15 141 1. 05 21 Control plus 1.0 g. Compound I plus 15 g. Compound III plus 0.25 g. Compound XVII 145 1.03 20 182 1. 05 15 166 97 .18 Control plus 1.0 g. Compound I plus 15 g. Compound III plus 1.0 g. Compound XVII 148 1.12 .22 186 1. l0 15 162 .96 20 Control plus 1.0 g. Compound I plus 15 g. Compound III plus 0.25 g. Compound XV 141 1. 17 18 178 1. 15 .15 148 1.07 23 T able D Original test 1 week incubation 2 week incubation Feature addenda, g./mole AgX Rel. Fog Rel. 'y Fog Rel. 'y Fog speed speed speed Control (contains 1.0 g. Compound I) 100 87 13 100 68 15 89 71 17 Control plus 0.75 g. Compound II plus 15 g. Compound III 138 1. 01 09 129 90 09 110 81 12 Control plus 0.75 g. Compound II plus 15 g Compound III plus 1.5 g. Compound IV 159 1.32 .12 166 1. 07 10 159 92 13 Control plus 0.75 g. Compound II plus pound III plus 1.5 g. Compound XIIL.- 166 1.22 12 166 85 16 138 82 22 Control plus 0.75 g. Compound II plus 1 ompound III plus 1.5 g. Compound XIV 166 1. 26 12 174 89 13 170 85 13 Table E Original test 1 week incubation 2 week incubation Feature addenda, g./mole AgX Rel. 'y Fog Rel. 'y Fog Rel. 'y Fog speed speed speed Control (contains 1.0 g. Compound I) 100 1. .15 102 70 15 102 66 .20 Control plus 10 g. Compound III plus 1.0 g. Compoun 166 1. 25 14 151 1. 0 11 129 87 .15 Control plus 10 g. ompound III plus 1.0 g. Compound IV plus 1.0 g. Compound II 162 1. 26 14 162 97 09 151 .84 .16 Control plus 10 g. Compound III plus 1.0 g. Compound IV plus 1.0 g. Compound IX 162 1. 23 13 151 .91 11 151 .86 15 Control plus 10 g. Compound III plus 1.0 g. Compound IV plus g. Compound IX 159 1.14 15 155 90 .13 174 82 13 Control plus g. Compound III plus 1.0 g. Compound IV plus 1.0 g. Compound X 162 1. 12 13 155 .88 .14. Control plus 10 g. Compound III plus 1.0 g. Compound IV plus 1.0 g. Compound XI 162 1. 27 14 159 97 11 155 .87 15 Control plus 10 g. Compound III plus 1.0 g. Compound IV plus 1.0 g. Compound XII 162 1. 15 155 93 11 159 .85 .14

Table F Original test 1 week incubation 2 week incubation Feature addenda, g./mole AgX Rel. 'y Fog Rel. 7 Fog Rel. 'y Fog speed speed speed Control (contains 1.0 g. Compound I) 100 83 .14 110 .92 .13 105 70 .15 Control plus 0.75 g. Compound II plus 10 g. Compound III plus 1.0 g. Compound IV 174 1. 31 10 178 1.14 11 159 99 .20 0.75 g. Compound II plus 10 g. Compound 111 plus 1.0 g. Compound IV 129 1.19 08 123 1.04 08 112 .90 15 0.75 g. Compound 11 plus 10 g. Compound III plus 1.0 g. Compound IV plus 1.0 g. Compound VII.-. 195 1.15 13 204 1. O6 14 166 98 28 0.75 g. Compound II plus 10 g. Compound III plus 1.0 g. Compound IV plus 1.0 g. Compound VI 186 1. 21 .14 209 1. l8 20 145 90 42 chemical sensitizer are used alone as the sensitizer in pho- 5 (b) a 3-pyrazolidone silver halide developing agent, tographic silver halide emulsions to increase the speed and of the emulsions, undesirable levels of fog are obtained, (c) a hydroquinone silver halide developing agent and such being well-known to those skilled in the art. HoW- a compound capable of forming a bisulfite ion. ever, increased speed can be obtained in accordance with 5. A photographic silver halide emulsion containing a the invention Without undesirable fog, by combining relasensitizing amount of a combination comprising:

tively small amounts of quarternary ammonium salt sensitizers with developing compositions as described and illustrated hereinabove.

The invention has been described in detail with particular reference to preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention as sensitizing amount of sensitizer combination comprising: (a) a quarternary ammonium salt silver halide chemical sensitizer; and

(b) a hydroquinone silver halide developing agent and a compound capable of forming a bisulfite ion. 2. A photographic silver halide emulsion containing sensitizing amount of a combination comprising:

(a) a quarternary ammonium salt silver halide chemical sensitizer,

(b) a 3-pyrazolidone silver halide developing agent,

and

(c) a hydroquinone silver halide developing agent and a compound capable of forming a bisulfite ion.

3. A photographic silver halide emulsion containing a sensitizing amount of a combination comprising:

(a) a his pyridinium salt silver halide chemical sensitizer, and

( b) a hydroquinone silver halide developing agent and a compound capable of forming a bisulfite ion.

4. A photographic silver halide emulsion containing a sensitizing amount of a combination comprising:

(a) a his pyridinium salt silver halide chemical sensitizer,

(a) a l-alkyl-1,1-dimethylhydrazinium salt silver halide chemical sensitizer, and (b) a hydroquinone silver halide developing agent and a compound capable of forming a bisulfite ion.

6. A photographic silver halide emulsion containing a sensitizing amount of a combination comprising:

(a) a l-alkyl-l,l-dimethylhydrazinium salt silver halide chemical sensitizer,

(b) a 3-pyrazolidone silver halide developing agent,

and

(c) a hydroquinone silver halide developing agent and a compound capable of forming a bisulfite ion. 7. A photographic silver halide emulsion containing a sensitizing amount of a combination comprising:

(a) .an a,walkylenebis(l,1-dime'thylhydrazinium salt) silver halide chemical sensitizer, and

(b) a hydroquinone silver halide developing agent and a compound capable of forming a bisulfite ion. 8. A photographic silver halide emulsion containing a sensitizing amount of a combination comprising:

(a) .an a,walkylenebis(1,l-dimethyihy-drazinium salt) silver halide chemical sensitizer, (b) .a 3-py-razoli-done silver halide developing .agent,

and

sensitizing amount of .a combination comprising:

(a) a bis pyridinium salt silver halide chemical sensi- :tizer,

(b) a hydrazinium salt selected from the group consisting of (1) an a,w-alkylenebis(l,l dimethylhydrazinium salt) silver halide chemical sensitizer, and

13 (2) a l-ialkyl-l;l-dimethylhydrazinium silver hali-de chemical sensitizer.

(c) a S-pyrazolidone silver halide developing agent,

and

(d) :a hydroquinone silver halide developing agent and a compound capable of forming a bisulfite ion.

10. A photographic gelatino-silver halide emulsion containing a sensitizer combination comprising:

(a) about .01 to 10 grams per mole of silver halide of 7,18-diaza-6,l9-dioxotetracosane-1,24-bis(pyridinium perchlorate), and

(b) about 1 to 100 grams per mole of silver halide of a mixture of hydroquinone and a minor proportionate amount of sulfur dioxide.

11. A photographic gelatin-o-silver halide emulsion containing a sensi-tizer combination comprising:

(a) about .01 to 10 grams per mole of silver halide of l-n-decyl-l,l-dimethylhydrazinium perchlorate,

(b) about .01 to 10 grams per mole of silver halide of 7,'l8diaza-6,19- di'oxotetracosane-l,24-bis(pyridinium perchlorate (c) about .01 to 1 grams per mole of silver halide of 4-methyl-l-phenyl-3-pyraz-olidone, and

(d) about l to 100 grams per mole of silver halide of a mixture of hydroquinone and a minor proportionate amount of sulfur dioxide.

12. A photographic gelatino-silver halide emulsion containing a sensitizer combination comprising:

(a) about .01 to grams per mole of silver halide of l-n-decyl-1, l-dimethylhydrazinium perchlorate,

(b) about .01 to 10 grams per mole of silver halide of 7,18-diaza-6,l9-dioxotetracosane-1,24-bi-s(pyridinium perchlorate) (c) about .01 to 10 grams per mole of silver halide of 4-methyl-l-phenyl-3 pyrazolidone, .and

(d) about 1 to 100 grams per mole of silver halide of a mixture of 2,5-dihydroxybenzoic acid and .a minor proportionate amount of sulfur dioxide.

13. A photographic silver halide emulsion as described in claim 1 wherein the quaternary ammonium salt silver halide chemical sensitizer is selected firom the group consisting of:

7, l 8-.diaz a-6, l 9-dioxotetracosane- 1 ,24-bis(pyridinium perchlorate),

14. A photographic silver halide emulsion as described in claim 1 wherein :the 3-pyrazolid'one silver halide dveloping agent is selected from the group consisting of:

4-methyl-1-phenyl-3-py-razolidone, Z-chloroacetyl-l-phenyl-S-pyrazolidone, 2-chlor-oacetyl-41methyl-1-phenyl-3-pyrazolidone, 4-ethyl-1-phenyl-3-pyrazolidone, 4-methyl-2-phenoxyacetyl-l phenyl-3-pyr.azolidone, 4-benzyl-l-phenyl-3-pyrazolidone, and 4-n-octyl-l-phenyl-3-pyrazolidone.

15. A photographic silver halide emulsion as described in claim v1 wherein the compound capable of forming a bisul-fite ion is sulfur dioxide.

16. A photographic silver halide emulsion as described in claim 1 wherein the compound capable of forming a bisulfite ion is an alkali metal 'bi-sulttite.

17. A photographic emulsion support having coated thereon a photographic silver halide emulsion as described in claim 1.

References Cited by the Examiner UNITED STATES PATENTS 2,419,975 5/47 Trivelli et .al. 96-66 2,940,851 6/60 Beavers et .al. 96-66 3,017,270 1/ 62 Treg-illus et al, 96-107 X FOREIGN PATENTS 845,928 8/60 Great Britain.

NORMAN G. TORCHIN, Primary Examiner. 

1. A PHOTOGRAPHIC SILVER HALIDE EMULSION CONTAINING A SENSITIZING AMOUNT OF SENSITIZER COMBINATION COMPRISING: (A) A QUARTERNARY AMMONIUM SALT SILVER HALIDE CHEMICAL SENSITIZER; AND (B) A HYDROQUINONE SILVER HALIDE DEVLOPING AGENT AND A COMPOUND CAPABLE OF FORMING A BISULFITE ION..
 2. A PHOTOGRAPHIC SILVER HALIDE EMULSION CONTAINING A SENSITIZING AMOUNT OF A COMBINATION COMPRISING: (A) A QUARTERNARY AMMONIUM SALT SILVER HALIDE CHEMICALA SENSITIZER, (B) A 3-PYRAZOLIDONE SILVER HALIDE DEVELOPING AGENT, AND (C) A HYDROQUINONE SILVER HALIDE AGENT AND A COMPOUND CAPABLE OF FORMING A BISULFITE ION. 